Leakproof recessed bottom carton



Feb. 19,v 1963 G. v. sKowRoNsKl 3,078,171

` LEAxPRooF REcEssED BOTTOM CARTON Filed May 26, 1961 l 3 Sheets-Sheet 1 3 (I4 37 l 35 49- 8 3a |95 3 3 4 56 K i qoq IOlw. |52 I6 I6 (I7 *s3 *7 l5 3 3 web s g ag ,5 le ls 3A llocl A lod) lob) |O.)

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Z GEORGE v sKowRo 5K1 i ATTOENEYS Feb- 19, 1963 G. v. sKowRoNsKl 3,078,171

LEAKPRO'OF .RECESSD BOTTOM CARTON Filed May 26, 1961 3-SheetsSheet 2 ATTORNEYS Fel. 19, 1963 G. v. sKowRoNsKl 3,078,171

LEAKPROQF RECESSED BOTTOM CARTON Filed May 26, 1961 3 Sheets-Sheet 3 INVENTOR. GEORGE v. sKowRoNsKl A TTOENEYS 3,078,171 LEAKPRF REQESSSED BOTTM QARGN George V. Skovvronski, Neenah, Wis., assigner to American Can Company, New York, NY., a corporation ot New .lersey Fiied May 26, 1961, Ser. No. 112,987 Z Claims. (Q1. QSL-171) This invention relates to a leakproof carton provided with a recessed bottom. More specifically, the invention may be used advantageously for the display of packaged food products.

Cartons and containers having recessed bottoms have been employed for a variety of purposes. For instance, paper cups which have the bottom recessed, are used for hot drinks with the recessed bottom preventing contact with a surface susceptible to heat damage. Round tubs or pails with recessed bottoms have been employed in the packaging of cottage cheese and ice cream to protect the product from ice or water in the bottom of the storage area. Present square or rectangular recessed bottorn cartons are available but generally have the shortcoming of not being suitable for packaging liquids. The construction of the carto-ns is such that the corners of the carton have a tendency to leak. While the round tub is leakproof, it has the disadvantages of being uneconomical with regard to storage space as well as having more limited printing areas.

Ideally, a recessed bottom carton or container should, in order to provide the desired versatility for food packaging, Iinclude the following features. The upright carton should be leakproof to the top edges thereof and capable of maintaining its leakproofness for a period of time. When a tight fitting closure is applied to the top, the carton should be leakproof when changed to an inverted position. A square or rectangular shape is desirable since it provides econo-my of storage space as well as increased printing areas. The strength of the Wall portions extending below the bottom of the carton should be sufficient to resist appreciable downward pressures on the carton without collapsing. For economy of operation in setting up the carton a single blank is ideal to reduce the number of steps required. Finally, the appearance of the finished carton should be suitable for display purposes thereby enhancing sales appeal.

it is a primary object of the present invention to provide a leakproo rectangular, recessed bottom carton that can readily be set up from an integral blank.

Another object of the present invention is to provide a rigid carton which is adapte-d to receive a tight fitting closure to make a totally leakproof package.

Still another object of the present invention is to provide a sealed carton having multiple printing areas which fully utilizes storage space and Yet another object of the present invention is to provide a reinforced leakproof carton having a neat appearance which enhances the Saleability of the packaged product.

A further object of the present invention is to provide a carton which has a tight fitting closure suitable for reuse and numerous reclosings.

According to the present invention a tapered rectangular leakproof carton with a recessed bottom is constructed from an integral blank. At least a double thickness in nited dtates @attent did Patented Feb. 19, i963 ine all of the carton walls provides a reinforced construction which resists forces which would crush or distort a carton of weaker construction. The finished carton in an upright position has no single or rough edges apparent because of the particular fold pattern of the blank employed in making the carton. Further, the carton blank need only be coated on one side for purposes of heat-sealing and leakproofness. The particular fold pattern is such that in the finished upright carton the inside surfaces of the carton as Well as the visible outside surfaces of the carton have the protective coating thereon. integral corner webs which extend to the upper edge of the side walls insure lcakproofness in the iinished carton, while a tight fitting closure in pressure contact with the lips or upper edge portions of the side walls maintains leakproofness when the carton is inverted.

'Further details, advantages and objects of the present invention will be apparent from the following specification and appended drawings wherein:

FIGURE 1 is a plan View of an integral blank suitably cut and scored to form a rectangular leakproof carton,

FiGURE 2 is a plan View of the blank shown in PIG- UiE l folded upon itself,

FIGURE 3 is a plan View of the blank shown in FIG- URE 2 partially set up,

FIGURE 4 is a fragmental perspective View of the same partially set up blank at a further stage in being set up,

FlGURE 5 is a perspective view of the completed carton,

FlG RE 6 is a sectional view of the set up carton taken along 6 6 of FIGURE 4, and

FlGURE 7 is a perspective View of the completed carton containing a food commodity and sealed with a tightly fitting closure.

Referring to FEGURE l, the carton is made of a single oldabie blank A of iiexible material, such as paperboard, provided with a gloss wax composition coating or other suitable materials such as polyethylene, rubber hydrochloride and the like, suitable for heat sealing. The

' blank is divided by score lines ida, lub-i9 into hingedly connected panels, lflaps, and webs including bottom panel dit, inner side panels 31, 38, outer side panels 32, side panel iiaps 35, di?, edge flaps 33, outer edge aps 3d, web portions 36, 37 and lip panels 39.

After the blank has been formed, the rst step in forming the carton is to infold outer edge flaps 34 and edge iiaps 33 about sco-re lines itin and lltib, respectively, to lie flat on the adjacent carton blank areas hingedly connected thereto. Next, outer side panels 32 with side panel flaps 35, di? connected thereto by score lines 16 are infolded about score lines lll to lie in superposed relationship on inner side panels 3l as shown in FIGURE 2. This View shows the bottom or outside of bottom panel 3Q. 5

in setting up the carton, the folded blank shown in FIGURE 2 is turned over and superposed inner and outer side panels 3i, 32 are infolded about score lines l2 with web portions 36, 37 hingedly connected together by score lines "ad folded outwardly. The infolding is continued until the lateral edges of inner side panels .il and 38, defined by score lines i7 and 19, respectively, abut. At this stage, which is shown in FIGURE 3, Web portions Se and 37 hingedly connected along score 3 lines i8, lie superposed against side panel flaps 3S, 40. The web portions 35 and 37 are then heat sealed together to provide a leakproof body delned by the side panels and bottom panel.

In order to complete the setting up, side panel flaps 4t) with web portions 36, 37 and outer edge flaps 3d superposed thereagainst are infolded against inner side panels 38 as shown in FIGURE. 4. 'Ihen side panel tiaps 35 with web portions 35, 37, and outer edge Flaps 34 superposed thereagainst are infolded about adjacent score lines 16 to lie superposed against the outer surfaces of side panel aps 4l). Finally, upstanding lip panels 39 are folded outwardly about score lines I4 to lie superposed against the upper edges of side panel flaps 35 and 40. Heat and pressure are then applied with lip panels 39 becoming heat-sealed to the upper edges of side panel flaps 35, 40, and side panel aps 3S becoming heat-sealed to flaps 40; The completed carton having a rigid, leakproof constructionis shown in FIGURE 5.

FIGURE 6 shows in section the bottom' construction of the carton. Bottom panel 30 is suspended up from the bottomedges ofi the carton a distance approximately equal to the difference in height between the inner side panels' 31 and the outer side panels 32. This distance can be varied asdesired merely by changing the height relationship between the inner and outer side panels. The bottom edges of the cartonare reinforced by the doubled thickness of the lower extremities of the carton adjacent to bottom edges; Double thicknesses inall of the carton side walls gives increased strength to the carton tending to prevent distortion due to packing and handling.

FiGURE 7 is a perspective view of the completed carton containing a commodity, for example potato salad, which is an item particularly well suited for vending machine packaging. A tightly fitting groove plastic closure 50 is employed to maintain the freshness of the particular commodity being packaged. In place of the closure 50, a` partial overwrap surrounding and adhered to the upper portion of the filled carton may be employed. Theidegree of opacity of the cover employed obviously depends upon whether or not the carton is used to display the commodity packaged in it.

Although the embodiment described employs paperboard with a heat-scalable coating thereon to obtain leakproofness, other means of making the carton according to the present invention leakproof may be employed. For instance,` the carton blank maybe made of uncoated paperboard and the blank set up by applying adhesive to the surfaces of lip panels 39and side panel aps 35 and 40. The step of sealing` the web portions 36 and 37 together may be omitted. After the carton is completed, a thin membrane of liquid proof material, such as polyethylenemay be applied to the interior surfaces of the carton. Another method would'be to spray the interior surfaces of the completed uncoated paperboard carton with a thin plastic lm. Since the steps of either adding a membrane to or spraying a plastic lilm on the inner surfaces of the carton are more costly then employing coated paperboard blanks, the particular embodiment described in detail herein is preferred.

The appearance of the carton according to the present invention can be considerably enhanced if the paperboard blank is laminated with a layer of metal foil. Since in the finished carton only the inside surface of the original blank shows, the foil need be applied only on one surface of the original blank. The side of the original blank opposite the foilmaybe coated with a heatscalable adhesive and the carton set up as previously described. The use of a foil covered blank is particularly advantageous for display packaging and when the carton contains a commodity that the consumer will use over av period of time so that the carton will be viewed a number of times.

Although the embodiment as described employs a heat scalable adhesive for securing the side panel flaps and lip panels, other means such as locks or staples may be employed. For instance, side panel iiaps 55 and rtimay` have cooperating male and female locking means thereon which when the aps are infolded engage in locking relationship. The use of staples is advantageous when the carton is constructed of uncoated paperboard and a plastic membrane coated of the inside of the completed carton to render it leakproof.

The present invention provides a web corner carton construction which makes the carton leakproof. When the web portions are sealed together adjacent their connection to the side panels, wicking of the liquid into the upper edges of the web portions is prevented. The rectangular construction provides a larger printing surface than does a round tub. Double thickness side walls of the carton give a carton construction which resists large compression forces such as would be applied to a carton on the bottom of a stack of loaded cartons on trays. Furthermore, a rectangular carton is more economical to store in terms of capacity per amount of storage space required. Also, the integral carton blanks may be set up readily by hand or machinery.

It is to be understood that the size and the shape of the carton and the material from which it is formed may be varied in numerous waysby` those skilled in the art without departing from the spirit of the invention.

I claim:

l. A tapered, recessed bottom, leakproofl carton formed of a single blank suitably cut and scored to pro vide a carton having a bottom panel, two pairs of opposed trapezoidal shaped inner side panels of essentially equal configuration hingedly connected to the edges of said bottom panel, a pair of trapezoidal shaped opposed outer side panels hingedly connected to the upper edges of the first pair of said inner side panels-and lying superposed thereagainst and extending an appreciable distance below the bottom panel with-the side edges-of the outer side panels essentially coextensive with the side edges of saidinner side panels, two component webs hingedly connected to the adjacent side edges of said inner side panels with each of said webs having a diagonal score line connecting said components and folded to lie superposed against the second of said pair of inner side panels, said web components being sealed together along their hinge connection to the adjacent side edges of theinner side panels, a pair of opposed edge flaps hingedly connected to the bottom-edges of said outer side panels and lying in subposed relationship therewith with the upper marginal portions thereof lying between said first pair of inner side panels and said outer side panels, side panel aps hingedly connected to the side edges of the outer side panels and forming outer side walls lying superposed on the second pair of inner side panels in overlapping adhered relationship, outer edge flaps attached to the bottom edges of the closure aps and lying in subposed relationship therewith with the upper marginal portions thereof lying between said second pair of inner side panels and said side panel flaps, and a pair of opposed lip panels, hingedly connected to the upper edges of the second pair of inner side panels and lying superposed on the upper marginal portions of the outer side walls, said carton having its inner areas covered with a liquid proof layer.

2. A food package comprising a leakproof recessed bottom container having food products therein; said container being formed of a single cut and scored blank having a bottom panel; two pairs of opposed inner side panels of essentially equal configuration hingedly connected to the edges of said bottom panel; a pair of opposed outer side panels hingedly connected to the upper edges of the iirst pair of said inner side panels and lying superposed thereagainst and extending an appreciable distance below the bottom panel with the side edges of the outer side panels essentially coextensive with the side edges of said inner side panels; two component webs hingedly connected to the adjacent side edges of said inner side panels with each of said webs having a diagonal score line connecting said components and folded to lie superposed against the second of said pair of inner side panels, said web components being sealed together along their hinge connection to the adjacent side edges of the inner side panels; a pair of opposed edge aps hingedly connected to the bottom edges of said outer side panels and lying in subposed relationship therewith with the upper marginal portions thereof lying between said rst pair of inner side panels and said outer side panels; side panel flaps hingedly connected to the side edges of the outer side panels and forming outer side walls lying superposed on the second pair of inner side panels in overlapping adhered relationship; a pair of opposed lip panels hingedly connected to the upper edges of the second pair of inner side panels and lying superposed on the upper marginal portions of the outer side walls; said container having its inner areas covered with a liquid proof layer and having a securely tting top closure to preserve the freshness of said perishable food.

References Cited in the file of this patent UNITED STATES PATENTS 736,955 Garman Aug. 25, 1903 2,279,670 Ford et al Apr. 14, 1942 FOREIGN PATENTS 202,503 Great Britain Aug. 23, 1923 

2. A FOOD PACKAGE COMPRISING A LEAKPROOF RECESSED BOTTOM CONTAINER HAVING FOOD PRODUCTS THEREIN; SAID CONTAINER BEING FORMED OF A SINGLE CUT AND SCORED BLANK HAVING A BOTTOM PANEL; TWO PAIRS OF OPPOSED INNER SIDE PANELS OF ESSENTIALLY EQUAL CONFIGURATION HINGEDLY CONNECTED TO THE EDGES OF SAID BOTTOM PANEL; A PAIR OF OPPOSED OUTER SIDE PANELS HINGEDLY CONNECTED TO THE UPPER EDGES OF THE FIRST PAIR OF SAID INNER SIDE PANELS AND LYING SUPERPOSED THEREAGAINST AND EXTENDING AN APPRECIABLE DISTANCE BELOW THE BOTTOM PANEL WITH THE SIDE EDGES OF THE OUTER SIDE PANELS ESSENTIALLY COEXTENSIVE WITH THE SIDE EDGES OF SAID INNER SIDE PANELS; TWO COMPONENT WEBS HINGEDLY CONNECTED TO THE ADJACENT SIDE EDGES OF SAID INNER SIDE PANELS WITH EACH OF SAID WEBS HAVING A DIAGONAL SCORE LINE CONNECTING SAID COMPONENTS AND FOLDED TO LIE SUPERPOSED AGAINST THE SECOND OF SAID PAIR OF INNER SIDE PANELS, SAID WEB COMPONENTS BEING SEALED TOGETHER ALONG THEIR HINGE CONNECTION TO THE ADJACENT SIDE EDGES OF THE INNER SIDE PANELS; A PAIR OF OPPOSED EDGE FLAPS HINGEDLY CONNECTED TO THE BOTTOM EDGES OF SAID OUTER SIDE PANELS AND LYING IN SUBPOSED RELATIONSHIP THEREWITH WITH THE UPPER MARGINAL PORTIONS THEREOF LYING BETWEEN SAID FIRST PAIR OF INNER SIDE PANELS AND SAID OUTER SIDE PANELS; SIDE PANEL FLAPS HINGEDLY CONNECTED TO THE SIDE EDGES OF THE OUTER SIDE PANELS AND FORMING OUTER SIDE WALLS LYING SUPERPOSED ON THE SECOND PAIR OF INNER SIDE PANELS IN OVERLAPPING ADHERED RELATIONSHIP; A PAIR OF OPPOSED LIP PANELS HINGEDLY CONNECTED TO THE UPPER EDGES OF THE SECOND PAIR OF INNER SIDE PANELS AND LYING SUPERPOSED ON THE UPPER MARGINAL PORTIONS OF THE OUTER SIDE WALLS; SAID CONTAINER HAVING ITS INNER AREAS COVERED WITH A LIQUID PROOF LAYER AND HAVING A SECURELY FITTING TOP CLOSURE TO PRESERVE THE FRESHNESS OF SAID PERISHABLE FOOD. 